Flood Maps Explained

Determining the Risk

To identify a community’s flood risk, FEMA conducts a Flood Insurance Study. The study includes statistical data for river flow, storm tides, hydrologic/hydraulic analyses, and rainfall and topographic surveys. FEMA uses this data to create the flood hazard maps that outline your community’s different flood risk areas.

Floodplains and areas subject to coastal storm surge are shown as high-risk areas or Special Flood Hazard Areas (SFHAs). Some parts of floodplains may experience frequent flooding while others are only affected by severe storms. However, areas directly outside of these high-risk areas may also find themselves at considerable risk.

Understanding Your Area

Changing weather patterns, erosion, and development can affect floodplain boundaries. FEMA is currently updating and modernizing the nation’s Flood Insurance Rate Maps (FIRMS). These digital flood hazard maps provide an official depiction of flood hazards for each community and for properties located within it.

FEMA has published almost 100,000 individual Flood Insurance Rate Maps (FIRMs). See your map and learn how to read it so you can make informed decisions about protecting your property, both financially and structurally.